Besides ‘living shells’ with occupants in residence and shiny recently-vacated shells, there is a third category of shell: the skeleton. I am sure there’s a better or more technical word for these. They aren’t fossils in the strict sense of remnants from a past geological age, but merely worn by the waves and bleached by the sun over time. Here are two examples (from different beaches) which show the intricacy of the part of the shell you don’t normally see: the interior

A shell skeleton from Little Harbour, in situ on the beach on a cloudy day

The same shell washed, with a wonderful pink tinge in sunlight

A strange corkscrew skeleton shell from Sandy Point. I’ve no idea what it is, nor how any creature can have lived in or around it, nor what it must have looked like when complete. Any ideas? Please use the comment box… Thanks, Kasia, for your ID of both as conch skeletons. The first obviously is, but the second puzzled me… until she pointed out that conchs build their own shells round themselves to their own designs rather than go to the one-stop conch shell shop. So if a conch starts wrapping itself comfortably round its own corkscrew, this is what you get

(Mrs rh quite rightly points out that my shell photos are unhelpful without a ruler to give an idea of size. Point taken. Too late. These are medium size…)